Spotlight: Stem Cell Pioneer

March 2006

When Treena Livingston Arinzeh cultures adult stem cells, she sees much more than the lab experiments to which she has devoted countless hours. She sees healing. She sees a child with an injured spine receiving an injection of stem cells that regenerate healthy tissue and allow that child to walk away from a wheelchair.

In 2003, the National Science Foundation (NSF) also gave Arinzeh its most prestigious honor — a Faculty Early Career Development award that included a $400,000 research grant. The NSF called her one of the “nation’s best young scientific researchers.”

After she won the Presidential award, U.S. Congressman Robert Menendez commended Arinzeh’s achievements by reading them into the Congressional Record. “I rise today to honor Treena Livingston Arinzeh for her outstanding work in the field of stem-cell research,”Menendez said on the floor of the House of Representatives. “Today, I ask my colleagues to join me in honoring Arinzeh, a trailblazer in the field of stem-cell research. New Jersey and our nation will greatly benefit from her groundbreaking work.”

At the forefront of therapy

What is it about Arinzeh’s research that has caught the attention of the NSF, President Bush and Congressman Menendez? In addition to its great future promise, her efforts have already yielded two very significant discoveries. Arinzeh has shown that stem cells can help to regenerate bone tissue, and she has proven that stem cells taken from one person can be implanted in another individual without being rejected.

William Hunter, chair of NJIT’s Department of Biomedical Engineering, heads a program that is advancing therapeutic innovation in many areas, including research into the potential of adult stem cells. According to Hunter, Arinzeh’s research is unique in that she has had success in crafting the right environment for controlling what kind of cells stem cells will develop into — nerve, bone or cartilage, for example. “Treena is working in a world that is at the forefront of medical therapy,” he says.

It was only a decade ago that scientists discovered the potential of adult stem cells. Produced by the body in an undifferentiated state, stem cells eventually specialize through natural processes to build and maintain specific tissues and organs. For research purposes, stem cells can be obtained from sources that include embryos, bone marrow, the brain and spinal cord, and intestines. Arinzeh works only with stem cells taken from adult bone marrow. So the controversy over the ethical implications ofembryonic stem-cell research, in her case, is moot.

To put it simply, when harvested for research outside the body, stem cells don’t know what they want to be when they grow up. Arinzeh aims to provide them with the guidance they need to become different types of cells useful for repairing injuries and curing disease.

The list of conditions for which stem-cell treatment holds promise grows almost daily. It now includes Parkinson’s, diabetes, Alzheimer’s, cancer and traumatic brain injury. But given the publicity and controversy swirling around stem cells, peopleoften don’t realize that the research is still at an early stage. It will take years before stem-cell research translates into medical applications that can help the sick or injured. Stem-cell research is in a stage comparable to that of the semiconductor industry during the 1940s, Arinzeh says — filled with potential but at least five or ten years from becoming a viable medical therapy.

Arinzeh, at age 34, has pushed the basic science of stem cells forward and she has a chance of taking it another step. “Treena has all the earmarks of a technical superstar,” says Michael Jaffe, professor of biomedical engineering and chemistry at NJIT, who was a research fellow at Hoechst Celanese Corporation before entering academia. “If anyone can take stem-cell research forward, she can,” he adds. “The odds of her, or of anyone, doing that is like playing the lottery. The odds are against you, but they are a lot worse if you don’t buy a ticket. Treena has a ticket.”

Two winning discoveries

As mentioned earlier, Arinzeh has already made two stem-cell breakthroughs. Several years ago, her paper in the Journal of Biomedical Materials Research documented the first of these discoveries. The paper focused on her work with biomaterials known as scaffolds — specifically, calcium phosphates — that act as a framework for growing stem cells and which can prompt them to become the cellular building material of bone or other tissues. Arinzeh conducted cell-culture experiments and studies of rats with bone defects that showed how the biomaterials stimulated stem cells to produce new bone tissue and repair the animals’ bones.

Her findings could help cancer patients who’ve had tumors removed from their bones, and who may even face the amputation of an affected limb because the diseased area is so extensive. Conceivably, therapy resulting from Arinzeh’s work could repair such damage by regenerating bone tissue. This approach could also help osteoporosis patients who have fractured bones. Other biomaterials she is testing might lead to therapies to repair cartilage, tendons and neuronal tissue.

This research may sound like science fiction, but Arinzeh’s lab techniques are fairly standard. She mixes human blood extracted from bone marrow with a special liquid and uses a centrifuge to separate the stem cells. Arinzeh then puts those cells in a culture dish, where they grow on top of a thin film of scaffold material. “I wait a few weeks and look for the properties I want,” she says.

Arinzeh’s second discovery, which she described in a paper for the Journal of Bone and Joint Surgery, was that adult stem cells taken from one person could be implanted in another without being rejected. Scientists had thought that the recipient’s immune system would reject such donor cells. It was among the most significant findings in stem-cell research in the past few years.

Partners in research

Arinzeh has formed key research partnerships across New Jersey. In addition to NJIT’s Jaffe, she is collaborating with orthopedic surgeon Louis Rizio on a project that uses stem cells to repair cartilage. Rizio is affiliated with the University of Medicine and Dentistry of New Jersey (UMDNJ), which is funding the research. They have also applied to the National Institutes of Health for additional funding.

Arinzeh has teamed with another orthopedic surgeon, Sheldon Lin, to investigate the use of stem cells for bone repair in diabetic patients. She also does research with Joachim Kohn, who directs the New Jersey Center for Biomaterials. The two are studying how polymers interact with stem cells, possibly to repair bone, cartilage, and even neurons in patients suffering from brain injuries.

The makings of an engineer

Arinzeh didn’t set out to be a stem-cell pioneer. Born and raised in Cherry Hill, New Jersey, Arinzeh attended the public schools there. Her mother was a high-school teacher and her father worked as a biochemist. In high school, her favorite subjects were math and science. Her high-school physics teacher, a mentor, told her she had the makings of an engineer.

A mechanical engineering major at Rutgers University, she became involved with rehabilitative engineering during a summer internship at the University of California at Berkeley. During that internship, she saw how engineers used technology to help the handicapped through prosthetic devices and other means. She loved the experience, and it started her on the path to a master’s degree in biomedical engineering at Johns Hopkins and a PhD at the University of Pennsylvania.

Instead of teaching, Arinzeh’s first job after completing her doctorate was as a product-development engineer at Osiris Therapeutics, a biotech company in Baltimore that specializes in stem-cell based therapies. She wanted to see how stem-cell products were developed, from research to clinical trial, to the marketplace. There, she saw firsthand the promise and limitations of stem-cell research.

Osiris researchers had made significant strides with stem cells, and even conducted a Phase One clinical trial using them to repair bone in the human jaw. But they couldn’t overcome one obstacle. Stem cells can indeed turn into cartilage and bone tissue, but to do so they need something to which they can adhere, and which will consistently prompt them to become the type of cells desired for therapy.

“Finding the right scaffold, that’s the trick,” Arinzeh says. “Companies doing stem-cell research didn’t know how to identify the right scaffold. At Osiris, this was a major limitation.”

To overcome this limitation, Arinzeh returned to academia. In 2001, she joined the faculty at NJIT, where much of her effort is focused on using calcium-phosphate scaffolds to promote stem-cell growth and differentiation. While Arinzeh has achieved considerable success, much work remains to be done with respect to understanding and directing the processes involved. It might take five years; it might take ten. But Arinzeh is confident that one day she’ll find the “trick” that will lead to therapeutic trials in a clinical setting.

In the end: hope

Suwah Amara, an African-American woman with a rare bone disease, is just the kind of person Arinzeh seeks to encourage academically, and to help through her research. A student in Arinzeh’s biomaterials class, Amara is a 22-year-old biomedical-engineering major. She has fibrous dysplasia, which makes her bones so brittle that they can fracture with the slightest exertion.

“My bones break so easily,” says Amara in a straightforward way, without self-pity. “I broke the bone in my upper arm five times. I’ve broken both my thighbones. The bone in my lower leg has broken so many times I’ve lost count.” One time, the simple task of uncapping a pen broke her forearm.

Once, after class, Amara asked Arinzeh if stemcell research might help cure her brittle bones. Arinzeh spoke with Amara about stem cells and gave her names of researchers who might be working on fibrous dysplasia.

That gave Amara hope. “It’s admirable that Dr. Arinzeh is trying to help people like me,” Amara says. “One day, I’d love to be able to walk without crutches.” In Amara’s eyes, Arinzeh is a role model as well. That Arinzeh, a young black woman, received the Presidential award “strengthens the hope of all minority women that we, too, can excel in research,” Amara adds.

But Arinzeh’s relationship with Amara is mutually beneficial. For in the end, it’s knowing people like Amara, with her determination to succeed and yearning to walk unimpaired, that motivates Arinzeh to continue spending all those hours in the lab.